Paper strap and method for making same



July 28, 1959 H. K. STEEN 2,896,397

PAPER STRAP AND METHOD FOR MAKING SAME Filed May 25, 1955 3 Sheets-Sheetl INVENTOR.

Hcrford K. Sreen Arromvn July 28, 1959' sTEEN 2,896,397

PAPER STRAP AND METHOD FOR MAKING SAME Filed May 25, 1955 s Sheets-Sheet2 INVENTOR. Hdrford K. Steen A TTORNE Yj y 1959 H. K. STEEN 2,896,397

PAPER STRAP AND METHOD FOR MAKING SAME Filed May 25, '1955 5Sheets-Sheet s Fig. 14.

Fig. I 15.

INVENTOR.

Hqrford K. Sfleen ATTORNEYS United sates Hal-ford K. Steen, Newburgh,N.Y., assignor, by mesne assignments, to Interstate Bag Company, Ina, acorporation of Virginia Application May 25, 1955, Serial No. 510,894

9 Claims. (Cl. 57-l'54) This invention relates to paper straps orribbons and the manufacture thereof. While paper straps or ribbonsaccording to the invention are adapted for a wide variety of uses, sometypes have been contrived especially for use as handles for papershopping bags and will be illustratively described in connection withthat use.

For many years standard shopping bag handles have been made of papertwisted into a twine of circular cross section, and these have beensecured to one or more walls of the paper bag by the use of suitableadhesive, or by mechanical means such as staples. There are a. number ofobjections to handles of this type.

A handle of small circular cross-section, given a sufiiciently heavyload within the carrying capacity of present day shopping bags, has thedrawback of digging into the hand and making a loaded bag uncomfortableto carry. Since the handle ends moreover, make only a line of contactwith a flat surface, it is diflicult to secure them to the bag walls,and thus far the most satisfactory means for attachment is to bind thehandle ends to the bag walls by the use of a strong paper strip runningparallel to the top of the bag which is pasted to the bag over thehandle ends. The amount of paper strip thus used is considerable and theoperation of putting on the strips (or patches) adds substantially tothe cost of the finished bags.

Flat handles are thus preferable to round handles, but flat paperhandles as heretofore constructed have also been subject to importantshortcomings, especially since under certain stresses such as occur whena heavily loaded bag is swung or twisted, the outermost fibers of thehandle fail in tension unless excess material is em ployed. In thisrespect all previously known flat handles are inferior to theconventional round type.

In accordance with the present invention a novel form of fiat handle isprovided which combines into one structure adequate and. uniformstrength, economy of material and manufacture, strong and dependableadhesive union with the flat bag body, a comfortably broad carryingsurface, and a satisfactory degree of flexibility.

The handle of the present invention is desirably formed of a strong,flexible paper such as kraft paper, although other forms of paper oreven plastic sheet material may be used.

Strong paper, such as kraft, the use of which is preferred, consistsalmostentirely of matted or felted cellulose fibers, plus such residuallignin and sizing material as may be present. Under the conditions ofthe present method, i.e., of moisture and pressure, the paper stripstarted with may be reshaped and caused to retain substantially anyshape desired due to interlocking folds or flutings that are formed andaided by a certain degree of re-orientation and re-bonding of thefibers.

The paper strap or ribbon of the present invention is desirably formedby continuously feeding and simultaneously twisting a web of flat,water-impregnated paper into a loosely twisted or spiral form (loose ascompared atent 2,896,397 Patented July 28, 19,59

with the tightness required for the making of twine) and at the sametime compressing and forming the twisted web into a ribbon of uniformthickness from edge to edge (or at least one having blunted side edges)through the application of suitable forming and confining pressure,which ribbon has a width several times as great as its thickness, butonly a fraction of the width of the original web which was twisted toform it.

In addition to the advantages pointed out above, a ribbon of this kindhas the additional merit that it can be pre-formed with localdeformations for special purposes as required.

Tears are most likely to start in the side edges of a flat ribbon. Thisis particularly true if the edges are thinner than the main body, andalso if the edges are under abnormal strains as compared with theremainder of the structure. The novel ribbon of this invention has theadvantage that it may be formed so as to be extremely resistant totransverse tearing, both because the extreme marginal portions are atleast as thick as any other portions of the ribbon, and because the edgeportions are free from abnormal peripheral strain and do not thereforepresent a condition favoring incipient tears.

While emphasis has been put upon ribbon-like structures having especialutility as bag handles, the invention is not confined to structureshaving flat faces nor having as great disparity of width to thickness asindicated above. A twine which is loosely twisted, fed, and continuouslycompressed by a pair of feeding and forming rollers has the advantageover conventional twine which is shaped solely by twisting that theperipheral fibers are free from circumferential strain. My improvedstrap may range in cross-section from elliptical to rectangular and inevery such form it presents a broad face for engagement with the hand.It will be noted that since the twisted web reaches the rolls in a formhaving a substantially circular crosssection, the shape of the resultingproduct must be such that it has greater width than thickness, and theforming space between the rolls must be correspondingly shaped. It isnot essential that the product be of uniform thickness from edge toedge, nor that it be of maximum thickness throughout the centrallongitudinal zone. The twine or ribbon may be longitudinally ribbed onone or both faces, or it may be thick along its margins andcomparatively thin along the longitudinal central zone. It may also benon-uniform in cross-section along its length, as for example, it may beof oval, or of substantially round cross section with end portions orother zones formed of flattened rectangular cross-section.

For a complete understanding of my invention, refer ence may now be hadto the following detailed description taken with the annexed drawings inwhich- Figs. 1, 2 and 3 show on an enlarged scale the strap materialwhich has been remoistened and has been care fully unfolded;

Fig. 1 shows the material of a strap which, before twisting, consistedof a two-ply web, the web having been folded on itself along alongitudinal axis;

Fig. 2 shows the material of a strap which, before twisting, consistedof a single-ply web;

Fig. 3 shows the material of a strap like that of Fig. 2 but with thematerial progressively unwrapped more and more toward the lower endthereof;

Fig. 4 is an end view of the material of Fig. 1, looking up the sheet,as indicated by the line 44 and the associated arrows;

Figs. 5 and 6 are end views of the material of Fig. 3, looking down andup the sheet, respectively, as indicated by the lines 55 and 6-6, andthe associated arrows;

Fig. 8 is a view on line 88 of Fig. 7 showingthe.

combination of die-and-draw rolls;

Fig. 9 is a view showing die-and-draw rolls appropriately shaped formaking an improved strap or strap segment of elliptical cross-section;

Fig. 10 shows a further modification of die-and-draw rolls for producinga further modified product;

Fig. 11 is a view similar to Fig. 7, showing an alternative apparatusand process;

I Fig. 12 is a plan View of a form of strap illustrative of theinvention, having broad, fiat ends,- and a comparatively thick andnarrow intermediate portion;

' Fig. 13 is a plan View of a form of strap, illustrative of theinvention, having comparatively thick and narrow ends, and a broad, flatintermediate portion;

Fig. 14 is a view in elevation of a bag, partly broken away, and brokenaway intermediate its ends for compactness, in which the strap of Fig.12 is utilized as a handle;

Fig. 15 is a fragmentary view in elevation of a bag, partly broken away,in which the strap of Fig. 13 is used as a handle.

Referring to Fig. 7, a reel of water-impregnated kraft paper web isshown at It the same being mounted for rotation about an axis a-a normalto its end faces so as to unroll the same, and simultaneously forrotation about a second axis b-b at right angles to the first, and whichextends in the direction of web feeding, for imparting a twist to theWeb. The web may be a single ply web or a plural ply web, i.e.,longitudinally folded, or even composed of a plurality of distinct,superposed plies, but in every instance a single winding is formed priorto shaping. The 'web is continuously withdrawn from the roll 10 and fedbetween a pair of rolls 11, 11a which function both as draw rolls forunrolling and advancing the web, and as die rolls for shaping andcompressing the web under a very substantial pressure. The rolls 11 and11a are driven in opposite directions to one another by means not shown.Such means are, however, capable of bringing rolls 11, 11a together withconsiderable force, and enable the rolls to move toward one another therequisite amount to assure the firm compression and molding of thetwisted web into a compact ribbon of rectangular cross-section. Theengagement by said rolls 11, 11a of the paper causes the same to bewithdrawn from the reel 10 by causing the reel to rotate about its axisaa. The reel 1% is also rotated about axis bb which extends parallel tothe direction of feed of the ribbon 12, thereby twisting the tape into ahelical form which assumes a narrowing, conical shape as it approachesthe draw rolls 11, 11a.

The rolls do not exert a mere flattening pressure upon the paper conebut serve rather,by confining the paper, to shape and form the twistedpaper into a ribbon 12 of rectangular cross-section, pressing the upperand lower surfaces toward one another, but also confining and formingthe side surfaces. This is accomplished by forming a molding spacebetween the peripheries of the rollers. The roller 11a is formed with acircumferential groove 13 of rectangular cross-section. The roller 11 isof simple cylindrical shape and has its marginal portion adapted to fitsnugly between the parallel side walls of the groove 13, as shown inFig. 8. This causes the twisted paper to be gathered and formed into aplurality .of creases or flutings A, which extend in from the end of theweb, and B, which extend in from the right edge of the web. All theilutings would eventually run off at the left edge if the strap were notcut off into lengths. The flutings interfit with one another to form acompact, flexible, square-cornered band or strap 12, as shown in Fig. 4.Because of the interfitting of the various longi- 4 tudinal folds orflutings, and the strong character of the paper employed, the strap 12possesses great strength, especially since some molding of thenon-fibrous materials and some interbonding of the many surfaces incontact with one another takes place.

The formation of the strap is facilitated by moistening the paper webprior to the action of the rolls 11, 1111. In the method illustrated inFig. 7, the web is moistened prior to winding it onto the reel 10. It isthen fed to the rolls 11, 11a before it has had a chance to dry out.

In Fig. 1 the strap, now unfolded, was made from a two-ply web, andthese plies are still shown superposed in the figure. An upper fold Cjoins a lower fold D along a fold line B. Fold C terminates along lineE. The heavily compressed wet paper does not tend substantially torecover from the form to which it has been reshaped by the rolls 11,11a. The non-fibrous constituents of the paper, when dried, cause thepaper to become set and to retain the rectangular ribbon shape, whilepermitting the ribbon to be bent and folded as desired. The rolls 11,11a are knurled at F for the purpose of improving the traction upon thestrap and also to facilitate interbonding of the folds, suchknurling-resulting in giving the strap a slightly ribbed effect asshown'in Fig. 3. The knurl marks persist when the strap has beenexfoliated. However, the knurling may, if desired, be omitted and asatisfactory result had.

As the strap is formed, it is cut into desired lengths by means ofcutting rolls 15, 16, the former being provided with a cutting blade15', and the latter having a hardened steel surface. The ribbon travelsto the cutting point at the linear speed of the edge of knife 15'.

The cut strips 12a of ribbon 12 are fed away from the cutting station bya segment 17 and a roller 18 opposed thereto. The segment 17 is oflarger radius than the radius of the cutting edge of the knife 15. Thesegment 17 is driven at the same rotary speed as the roll 15, and henceat greater linear speed than the knife edge. The parts are so timed thatthe leading end of the ribbon 12 is advanced beyond the couple 17, 18,while still free of the segment 17 and roll 18, prior to cutting. At theinstant of completion of the cut, the segment 17 proves effective toseize the cut length 12a and feed it forward at increased speed tosubsequent instrumentalities (not shown) which continue the advance ofthe strap at undirninished speed. The couples 11, 11a, 15, 16 and 17, 18are shown closer together than they are in actual practice.

The draw-die rolls act in an entirely diiferent manner from mereflattening rolls. Rolls of the latter type would effect a mere pressingaction, adapted to produce a ribbon having the cross-sectional shape ofa flattened tube. The action of the draw-die rolls of the presentinvention is an orderly folding and shaping of the material of theribbon into a series of interfitting longitudinally extending ilutingsin such a manner as to preserve the strength of the material and toprevent any tendency of the strap to elongate as by slippage of thefolds over one another. The compression of the ribbon to reduce itsthickness, tends to increase the width of the ribbon. This however, isresisted by the side walls of groove 13, so that in the end the ribbonis molded to the shape of the entire forming space.

The number of turns given the paper strip or ribbon may be varied withinlimits. Thus far I have found that.

from three to ten turns per linear foot of the complieted strip may beadvantageously provided, it being noted that the pitch is controlled bythe relation of the rate of feed of the draw rolls 11, 11a to the rateof rotation of the reel frame about the axis b-b. In Fig. 2 it will benoted that the piece of unfolded strap is placed with the flutingsubstantially vertical of the sheet, and 'with the longitudinal axis ofthe ribbon at a slight angle thereto.

Fig. 11 shows an alternate arrangement in which the paper ribbon 20 iswithdrawn from a roll 21, is moistened" in moistener 22, and formed intoa helix 20 by die rolls 23, 23a which are provided with two motions ofrotation, i.e., about the respective axes a'a, a"-a, normal to the facesof the rolls, and about an axis coincident with the longitudinal axis ofthe ribbon 20. The rollers 23, 2301 are duplicates of the rollers 11,11a. As in the case of Fig. 7, the strap having been formed by theaction of the rolls 23, 23a, such strap is severed by means of cutoffknife 24, and an opposed roll 25, similar to knife 15' and roll 16. Thecouple 24, 25 turns in unison with rolls 23, 23a about axis bb'. Theknife 24 is timed to cut the ribbon at the instant when the ribbon isflat; i.e., when the axes a--a and aa" extend horizontally. Segment 26and roll 27 duplicate the corresponding parts 17, 18 of Fig. 7.

The apparatus of Fig. 7 or of Fig. 11 is adapted to make a strap ofuniform width and uniform thickness, as shown in Figs. and 6. Such astrap is well adapted to serve as a bag handle. It provides fiat, broadends for adhesion to the bag body, and a flat, broad hand engagingportion. Straps of this: uniform, cross-sectional shape may be formed byvarying the shape of the forming space as seen in Figs. 9 and 10.

It is at times desirable to provide straps of varying cross-section. Anexample of this is shown in Figs. 12 and 14. The strap length 12b isshown of normal width and thickness in sections 30, but abnormally wideand abnormally thin in sections 31 and 32. The strap 12b, as seen inFig. 14 is applied to a wall of a paper bag 33 near the mouth thereof.The sections 31 and 32, which are wider than normal, are adhesivelysecured to the bag wall and to an overlying patch 34. The two outersections 30 extend vertically upward. The wide, thin sections 31 and'32are bent or folded. The section 30, which constitutes the hand gripportion, extends horizontally.

The strap 12b of Fig. 12 may be made on the machine of Fig. 7, or on themachine of Fig. 11 by suitable modification of the rollers 11, 11a or23, 23a. For forming the sections 30, the rolls 11, 11a would have thecrosssectional configuration shown between the rolls 39, 39a in Fig. 9,but wherever one of the wider, thinner sections 31, 32 is to be formed,the channel 13 of roll 11a would be widened to provide a forming spacelike that shown between rolls 40, 40a of Fig. 10, and the periphery ofthe roll 11 would be correspondingly widened. Wherever the channel iswider, the strap spreads into the wider span and automatically becomesthinner under the yielding pressure of the rolls 11, 11a.

Another variation is found in Figs. 13 and 15. Here the strip 120 isformed with ends 35 of normal width and thickness and with anintermediate body portion 36 which is extra wide and thin. The variationof crosssection is secured in the manner already pointed out by varyingthe shape of the forming space between the forming rolls. The strip 120is shown applied as a handle to a bag 37 in Fig. 15. The ends areadhesively secured to a bag wall and to an overlying patch 38.

As has been indicated, the uniform cross-sectional configuration of thestrip may be changed by uniformly changing the shape of the formingspace between the die-and-draw rolls. Fig. 9 shows the formation of astrap or twine 30 into elliptical or oval cross section. Die rolls 39and 39a, corresponding to rolls 11, lla'of Fig. 7, or to the rolls 23,23a of Fig. 11, are formed peripherally with complementary,semi-elliptical grooves whose major diameters extend axially of therolls, and whose minor diameters extend radially of the rolls. A strapof the character produced by these rolls has substantial practicaladvantages over ordinary twine, among them being (1) broader surfacecontact with the hand for a given cross-sectional area, (2) steeperpitch to the spiral convolutions and hence less tendency to elongate,and (3) looser twisting with resultant reduced circumferential tensionof the fibers.

The bath 22 through which the paper ribbon 20 passes prior to thetwisting and molding operations may, if desired, contain suitableadjuncts having a plasticising or other action. In many instances theuse of a diluted glycerine solution is advantageous in assisting thetwisting and molding operations. If desired suitable sizing or adhesivematerial may be used in the bath 22 to promote the bonding together ofthe fibers. In the operation of the method to date, no problem has beenpresented in the drying of the straps directly following theirformation, but it is obvious that the straps upon formation may besubjected to drying conditions if these are found necessary. Thepractice with die rolls 23, 23a may be operated at higher than roomtemperatures to increase the molding action if desired.

While certain preferred embodiments of the invention have beenillustrated and described in detail, it is to be understood that changesmay be made therein and the invention embodied in other structures. Itis not therefore, the intention to limit the patent to the specificconstruction illustrated, but to cover the invention broadly in whateverform its principles may be utilized.

I claim:

1. A paper strap consisting of a single winding of concurrently crumpledand loosely twisted paper having a plurality of twists per linear foot,and compressed along two cross sectional dimensions to a permanent formhaving a width of several times its thickness, but of appreciablethickness and with blunted side edges, the material of the strap beinglongitudinally folded in a plurality of fiutings extending in thegeneral direction of the longitudinal axis of the strap but making anangle thereto.

2. A strap according to claim 1 in which at least one side of the strapis knurled.

3. The strap according to claim 1 having from three to ten twists perlinear foot.

4. The strap according to claim 1 in which said material is kraft paper.

5. The strap according to claim 1, said. strap being of substantiallyrectangular cross-section.

6. A paper strap or ribbon as set forth in claim 1 in which the strap isof substantially elliptical crosssection.

7. A paper strap or ribbon as set forth in claim 1 having predeterminedmajor lengths of normal width and thickness, and other predeterminedlengths of greater than normal width and less than normal thickness.

8. The method of forming a paper strap which comprises, providing asingle broad web of strong, tough paper, impregnating the paper withliquid to render it appreciably plastic, twisting the wet web into aloose, helical form of high pitch, and progressively compressing thetwisted web transversely as it is twisted, while confining it laterally,to produce a strap of predetermined, permanent, compact flattenedcross-sectional configuration having a width several times itsthickness.

9. The method of forming a paper strap which consists in moisteningpaper or the like to render it appreciably plastic, twisting the paperloosely to form a single helix, and simultaneously with said twisting ofthe ribbon compacting the helix to form a solid flattened strap having awidth several times its thickness, said compression taking place in twodimensions crosswise of the strap.

References Cited in the file of this patent UNITED STATES PATENTS437,386 Williams Sept. 30, 1890 1,994,057 Wallach Mar. 12, 19352,037,205 Barnum Apr. 14, 1936 2,532,923 Kitchen Dec. 5, 1950 2,597,918Boersma et al. May 27, 1952

